I have some types I want to serialize as xml, but these types have read-only properties like:
public List<Effect> Effects {get; private set;}
but the xml serializer requires these properties to be writable.
Isn't xml serializer using reflection, so in effect can easily set these properties via reflection even though they are read-only?
Is there a way around this because I don't want these types to be editable by people, so the properties must be read-only, but I also want them to be xml serializeable.
Its not possible because As mentioned in MSDN
XML serialization is the process of converting an object's public properties and fields to a serial format (in this case, XML) for storage or transport.
But you can use DataContractSerializer. Here is a link to Marc's Answer on SO
Serializing private member data
Update
You can get over that behavior by leaving Auto Implemented properties and have somthing like this:
private List<Effect> _Effects;
public Effect()
{
_Effects= new List<Effects>();
}
public List<Effect> Effect
{
get
{
return _Effects;
}
}
Related
My boss have a strange request, he wants me to add a new function to serialize and deserialize all our products classes and add in the XML file all their property's types automatically.
I can't modify the classes to add new "types properties" before every "real property".
Is there a way to do this with [XmlAttributes] or something else ?
Thank you.
Maybe this is what you are looking for https://learn.microsoft.com/dotnet/api/system.xml.serialization.xmltypeattribute?view=netcore-3.1
this article describes the XmlTypeAttribute, which you can use to add a type attribute (in xml) on your properties tag.
[XmlType("aType")]
public string MyProperty {get;set;}
I do not think this is a duplicate. I have done some reading but did not find anything the same as this. It seems that fields can be serialized in binary formatters and in protobuf but not in XML. I don't know about JSON.
I am looking at replacing the standard .NET binary serializer with protobuf-net. The reason is to improve speed and get a smaller persisted file size.
In NET Binary I just marked the classes as serializable and left it at that. Not good I suspect.
With protobuf-net I need to specify what gets serialized with the [ProtoMember()] attribute. My newbie testing shows that private fields get serialized if so marked as do auto properties.
I do not want to change the class code definitions at all since I still need to be able to deserialize the old persisted data created by the NET serializer. I have a mixture of:
Private fields that get used inside the class
Private fields whose value gets set in constructors
Private fields that are backing fields for non automatic properties
Properties with the backing fields above
Auto properties
Properties with no setters that return some calculation or value determined internally
and probably some others. In other words pretty much every type of field and property.
I guess I need to persist any value that represents the state of the object that cannot be constructed after deserialization from the file.
I suppose there would be no harm in persisting every field and property but that would just make the job slower and the file bigger than it needs to be.
I think I can ignore private fields that are used only inside the class and are not set from outside.
I think I should persist those fields that are set in constructors.
I am not sure about backing fields - is it better to persist them or their public property?
I must persist auto properties
I can't persist properties with no setters so I need to persist whatever fields/properties get used in their calculations.
Am I on the right track or missing the point.
Thanks in advance.
We can't say what needs to be serialized. BinaryFormatter works on an "all fields" basis (unless they are explicitly marked not for serialization). You could use the same approach, but if you're using automatically implemented properties (which is fine) then note that you cannot add attributes to the backing field - unlike field-like events, the following is not valid c#:
[field:ProtoMember(1)] // not valid
public int X { get; set; }
This means that your only sensible choice is to decorate the property:
[ProtoMember(1)]
public int X { get; set; }
Because, if you change the automatically implemented property to a regular property, you will have broken BinaryFormatter's deserialization, since the field-name will have changed. That's fine, though - there's nothing wrong with marking either the fields or the properties (or both in the same type) for serialization. Another consideration on some platforms is accessibility: a private field may be inaccessible, where-as a public field works fine. And obviously public fields are pretty uncommon.
So:
decide what needs to be serialized (I can't tell you this)
mark it for serialization
do not change anything from automatically-implemented property to a regular property if you need BinaryFormatter to keep working (protobuf-net doesn't care if you change this)
in one project, I use datamember to serialize a class to an xml file, like,
[DataMember]
public string Member1;
later I query the xml to get one value out, like:
XmlNode1.SelectSingleNode("Member1");
Is it possible that make the Member1 above to a variable so when I change the DataMember name to be Member2 the Member1 in the query can be changed to Member2 automatically ,rather than I manually change it?
I am not exactly sure I understand what you hope to achieve, but I am thinking if you want to be able to centrally control the output from the serialization, you could define the tag in say a public static class.
static class SerializationConstants
{
public static string MemberTag = "Member1"; //or "Member2"
}
Then in your datamember you can use the property with the Name attribute.
[DataMember(Name=SerializationConstants.MemberTag)
public string Member1;
That would control serialization such that in your code for querying the xml, you can do something like:
XmlNode1.SelectSingleNode(SerializationConstants.MemberTag)
It would be a hack but I guess it should do if I understood your question correctly.
You should deserialize the XML file when working with it, then you can use field names to access properties and they would change if you would do refactoring.
This doesn't sound like a great idea.
If you are concerned about property names changing in your class with the DataMember attribute, you are probably going to want a layer of abstraction in the form of a DTO between that class and your XML querying. That way your XML querying class doesn't care if that member name changes or not because your DTO will never change. Just the mapping from the DTO to the volitle class.
I'm currently attempting to build a service to retrieve and serialize a Sitecore data item to JSON, so our Javascript code can access Sitecore content data.
I've tried serializing the object directly with JavascriptSerializer and JSON.Net; both broke due to recursion likely due to the various circular references on the child properties.
I've also attempted to serialize the item to XML (via item.GetOuterXml()), then converting the Xml to JSON. The conversion worked fine; but it only retrieves fields that were set on the item itself, not the fields that were set in the _standardvalues. I tried calling item.Fields.ReadAll() before serializing, as well as a foreach loop with calls to item.Fields.EnsureField(Field.id); however, neither resulted in retrieving the missing fields. However, debugging the code; the Fields array appears to contain all inherited fields from its base template as well as the ones set on the item; so I'm guessing GetOuterXml is just ignoring all fields that weren't set specifically on the item.
The more I look at this, the more it looks like I'm going to need a custom model class to encapsulate the data item and the necessary fields, decorate it with the appropriate JSON.Net serialization attributes, and serialize from there. This feels like a dirty hack though.
So before I go down this road; I wanted to know if anyone here had experience serializing Sitecore content items to JSON for client-side consumption, and is there an easier way that I'm missing. Any constructive input is greatly appreciated.
Cheers,
Frank
I would suggest pursuing your approach of creating a custom model class to encapsulate just the item data you need to pass to the client. Then serialize that class to JSON. This cuts down on the amount of data you're sending over the wire and allows you to be selective about which data are being sent (for security reasons).
The CustomItem pattern and partial classes lend themselves to this approach very well. In the code samples below, the .base class is your base custom item wrapper. You can use this class to access fields and field values in a strongly-typed manner. The .instance class could be used for JSON serialization.
By splitting out the properties you want serialized, you have granular control over the data being sent back to the requesting client and you don't have to worry as much about circular references. If you need to make any changes to field definitions, you could simply change your .base class with minimal impact on your JSON serialization.
Hope this helps!
MyCustomItem.base.cs
public partial class MyCustomItem : Sitecore.Data.Items.CustomItem
{
public const string TitleFieldName = "Title";
public MyCustomItem(Item innerItem) : base(innerItem)
{
}
public static implicit operator MyCustomItem(Item innerItem)
{
return innerItem != null ? new MyCustomItem(innerItem) : null;
}
public static implicit operator Item(MyCustomItem customItem)
{
return customItem != null ? customItem.InnerItem : null;
}
public string Title
{
get { return InnerItem[TitleFieldName]); }
}
}
MyCustomItem.instance.cs
[JsonObject(MemberSerialization.OptIn)]
public partial class MyCustomItem
{
[JsonProperty("Title")]
public string JsonTitle
{
get { return Title; }
}
}
I wonder if you wouldn't be better off using an XSLT to recursively build the JSON?
I ma using Newtonsofts' Json.Net to serialize some and array of objects to json.
The objects have a common set of properties but also have Meta property which is a dictionary
During serialization I want the key value pairs to be added to my json object as if they where root level properties, like this...
{
id: 1,
name:'jeff',
food:'spinch',
spoon: 'ýes'
}
Not like this:
{
id: 1,
name:'jeff',
meta:{
food:'spinch',
spoon: 'ýes'
}
}
I have dug through JsonSerializerSettings but cant seem to spot where I can jump in and override???
You can do this by creating your own JsonConverter and then adding an attribute to the class you want to serialize
[JsonConverter(typeof(MyConverter))]
Example here -
http://www.lostechies.com/blogs/rhouston/archive/2008/02/25/a-custom-converter-for-json-net.aspx
If your dictionary is a string to object dictionary could can simply use the [JsonExtensionData] attribute:
[JsonExtensionData]
public Dictionary<string, object> Meta { get; set; }
See How to serialize a Dictionary as part of its parent object using Json.Net.
You could use the .Net DataContractJsonSerializer.
For custom serialization, see:
http://msdn.microsoft.com/en-us/library/system.runtime.serialization.idatacontractsurrogate.aspx
One advantage of using IDataContractSurrogate (compared to simply adding properties to your class for serialization) is that you don't have to mix actual properties and serialization properties together in the same class.
Another advantage (compared to having to do custom serialization against a property bag, ala KeyValuePairConverter) is that you only have to add attributes to properties on your classes (the actual type and the surrogate type) and you can write all your conversion/custom serialization code directly against those types. This keeps your code higher level, and lets the framework deal with the exact transport mechanism.